Improvement in capping wood-screws



PATENT OFFICE.

GHARLES T. GRILLEY, OF NEW HAVEN, OONNEOTIGUT.

IMPROVEMENT IN CAPPING WOOD-SCREWS.

Specification forming part of Letters Patent No. 55,284, dated June 5, 1866.

To all whom it may concm:

Be it known that I, OHARLEs T. GRILLEY, of *New Haven, in the county of New Haven and State of Gonnecticut, have invented certai n new and useful Improvementsin Machincry for Oappin g Screws; and I hereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompanying drawings, in which- Figure 1 represents an isometrical perspective View of the machine constructed in accordance with my invention, and Fig. 2 a transverse vertical section of the same.

My invention relates to improvements in the method of capping screws for which Letters Patent wereissued to me on the 20th of April, 1852. By that method, after cuttin g and drawing up the cap in the usual manner, I nicked the cap to correspond with the nick in the screw, after which I applied the cap and closed it on the screw in the ordinary manner, as buttons and various articles of like nature are closed. But in so doing` the force required to close the cap on the screw also closed the nick in the cap, so as to leave no place in which to insert the screw-driver. It was then necessary to open the nick in the cap so as to correspond with that in the screw, which I did by placing the screw in a die, head upward, and then striking a hand-punch into the closed nick in the cap, thereby opening the same. This operation, however, had the effect to incline the cap to throw up from the face of the screw instead of remaining in close contact with the head upon which it had been previously closed. In order to obviate this difficulty I eventually conceived, and have at last perfected the present improvements in the mode of capping screws, which are substantially as follows:

After cutting, drawing up, and nicking the cap in the usual manner to correspond with the shape of the screw-head and the nick' therein, I then procecd to close the cap upon the head; but in order to prevent the closing up of the nick in the cap which, as above explained, will otherwise result from the operation, I mortise through the closing die or die-plate and insert therein acenter punch correspondingin shape with the nicls in both the cap and screw-head. This punch' rests on a screw which passes through a spring whose ends are supported in a recess formed in the bed-piece of the machine, as hereinafter explained, the object of this arrangement being to enable the punch to be adjusted in the die-plate, and at. the same time to yicld in some degree to the pressure of the drop or plun ger. When the ca p and screw (head down-ward) are placed in the closing-die the center punch passes through the nick in the cap into the nick in the screw-head, thus holding the two in position and entirely preventing the closing up of the nick in the cap when the drop is pressed upon the cap and screw, so that when the screw is taken from the die it presents. a perfect nick, rendering unnecessary the operation of again opening the nick with a hand-punch, as required by the old method, as above explained, and thereby et'- fecting a saving of both time and labor, and enabling me to cap screws at much less expense than formerly.

To enable those skilled in the art to understand and use my invention, I will now proceed to describe more particularly its nature and the manner'in which it may becarried into eff'ect by reference to the accompanyin g drawings.

The closing-die A is fitted in a corresponding recess formed for its reception in a bedpiece, H, which covers a recess in the platform G', formed for the reception of the spring D, as hereinafter explained. Through the center of the die A is a mortise, in which is inserted the center punch, B, which also extends downward through an opening in the bed-piece H, as seen in Fig. 2. i y

The spring D, which consists of an elastic strip of metal, is supported at each end in the recess g in the platform Gr, which recess may be deeper in the center than at the sides, so as to admit of the movement of the spring-plate D, and in the center of said spring-plate is a hole or openingjust under the openings in the y bed-piece H, through which is inserted the screw C. Around this opening or hole in the spring-plate D is attached a thicker piece of metal, d, whose interior surface is provided with a screw by means ot' which the screw O is held firmly in place. By turning this screw by its lower end, which extends through the bottom of the platform G, as shown in the drawings,its upper end may be either brought in contact with or withdrawn from the lower end of the center punch, B, and thus the punch may be adjusted to and held in the mortise in the closing-die A. i

In operatin g the machine the cap and screw (the latter head downward) are first placed in the closing-die A, so that the nick in the cap and the nick in the screw may both fit the 'nick is thereby prevented .from closingr During this operation the spring D, on which the punch rests, is of great use. Without the spring it would be impossible to use the punch in the die, owing to the fact that in case either of any imperfection in the screw itself or of any neglect of the operator to place the screw in its proper position in the die, the punch would be crushed andspoiled by the blow used in closing the cap firmly upon the screw-head. But with the spring the puuch is able to play up and down in the mortise in the closing-die, thereby adapting itself to any imperfeetions in the screw or other circumstances, as above indicatd. The base or lower end of the puneh may rest directly upon the spring-plate D but I prefer the arrangement shown in the drawings, whereby the screw O runs through the spring D, and the lower end of the punch rests upon said screw instead of directly upon the spring. The object of this arrangement is that When the end of the center punch which enters the nick in the screw becomes worn by continued friction, it can be screwed up into its place and raised without trouble by a turn of the screw U, upon which it rests, and henee- I am enabled to use one center punch for a long time, while without the screw I would be obliged to insert a new punch as oftenas the r one in use :should become in the least worn or imperfect.

Having thus described my improvements, what I claim .as my invention, and desire to secure by Letters Patent, is

' 1. In the manufactureof capped screws, placing the screw which is to be capped in an inverted position, or head downward, together with its eap,in the closing-die, constructed and arranged as described, so that the eap, while held in its proper relation to, may be closed on, the screw without disfiguring or closing up the nick in the cap, as herein shown and set forth.

2. In m'achinery for capping screws, as described, providiu g the elosin gdie with a punch, whereby the ready adjustment of the cap to the screw maybe effected, as herein shown and set forth. i

3. In machinery t'or capping screws, as herein set forth, the eombination of the closing-die and center puncl with the recessed plunger or drop, for joint operation as described, so that the cap may be adjusted to and closed in the screw while the nick in the cap is kept open,

as shown and set fortl'.

4:. In eombination with the elosing-die prowitnesses.

0; T. GRILLEY.

Witnesses:

LEONARD F. Monse, A. PoLLoK. 

